Climate in Sudan
Climate in Sudan
Until the secession of South Sudan in 2011, Sudan was the largest country in Africa, covering 8% of the continent’s surface. Even now, if you have the opportunity to travel across the country, you should do so: the scale and diversity of the land is striking. The Sudanese often describe their country as the whole of Africa in one country. It’s easy to understand why: Sudan ranges from desert in the north to mountains in the south, the whole bisected by one of the greatest rivers in the world. Straddling the fault-line between the Islamic world and sub-Saharan Africa – the Arabs call the country bilad as-sudan, or ‘land of the blacks’ – it is superlative in every sense.
Sudan is divided into four main geographical regions, roughly corresponding to the cardinal points. The country is tropical with both a rainy and a dry season, although the temperature and amount of rainfall depend greatly on location. North Sudan is desert and receives little or no rainfall. To the west is the Libyan Desert, part of the Sahara proper, and to the east is the barren Nubian Desert. It is whipped by dry northeasterly winds from the Arabian Peninsula and habob, summer afternoon dust storms that cut visibility to zero. It wasn’t always like this, however. Access to water was key to the rise of the Nubian kingdoms. Nile tributaries running through this region made the land lush, enabling them to raise cattle and accrue immense wealth – so much so, in fact, that they became an attractive target for Egyptian invaders from the north. Their civilisation fell victim to climate change around 300BC when arable land ceased to be viable. The desert has encroached ever since.
West Sudan is semi-desert, with rolling sand dunes and light grasslands that rise to the highlands of Darfur. There are no permanent rivers, only wadis (seasonal watercourses) that spring into life with the summer rains and leave rich alluvial soils behind. The Marrah Mountains in central Darfur are a range of volcanic peaks last active some 4,000 years ago. Their high-point, the Deriba Caldera, rises 3,042m above sea level, and the area enjoys a temperate climate with high rainfall and numerous springs. US geologists at the Center for Remote Sensing in Boston have identified an underwater lake three times the size of Lebanon that may in the future provide water to sufficiently irrigate the land and, as a result, resolve many of the conflicts linked to competition for resources.
East Sudan is dry grassland: the Gash Delta near Kassala acts as a seasonal drain for the region and produces rich grazing for the livestock of pastoral nomads. The barren spine of the Red Sea Hills separates the coastal plain from the rest of Sudan; the rising Ethiopian Plateau naturally demarcates the eastern border. Though all of Sudan becomes hot in the summer months, temperatures in Port Sudan climb higher still: summer highs of more than 50°C are not uncommon.
In the south are the Nuba Mountains, a remote region of South Kordofan that straddles the contested border between Sudan and South Sudan. The climate is semi-arid with a rainy season stretching from May to October. Rainfall is heaviest between June and September (as much as 15cm per month) and average temperatures, though slightly higher in the months before the rain, tend to vary very little.
blue nile bridge khartoum sudan by anthon jackson shutterstock© Anthon Jackson, Shutterstock
Sudan’s dominant geographical feature is the Nile. The Nile in Sudan is actually two rivers: the White and the Blue Niles, which converge in Khartoum before making slow progress north through Egypt and thence to the sea. Travelling within the country you inevitably spend much of your time following the river and the narrow strip of fertile land either side that holds back the desert.
Over 80% of the Nile’s water is provided by the Blue Nile, which rises near Lake Tana in the Ethiopian Highlands. The level of the river fluctuates with the seasons, reaching its height in July and August. The Blue Nile appears dark with rich alluvial silt (hence the name) – the fertile soil that allowed ancient Egypt to grow and prosper.
During the winter, the Blue Nile’s volume decreases considerably and the flow of the river is maintained by the slower waters of the White Nile. The ultimate source of the White Nile was a mystery for centuries and wasn’t settled until the 1860s when a series of expeditions by John Hanning Speke, James Grant and Henry Morton Stanley fully explored Africa’s Great Lakes region. The rains that fall on the Mountains of the Moon and drain from Uganda, Rwanda and Burundi into Lake Victoria provide the waters of the White Nile. The river traverses Uganda and South Sudan, where it is known as Bahr al Jabal, before finally entering Sudan south of Rabak.
The reason for the problem in tracing the source of the Nile is that it enters the Sudd, a labyrinth of waterways and papyrus that makes up a swamp the size of Belgium. The name ‘Sudd’ means ‘barrier’ in Arabic and it proved so formidable that explorers searching for the source chose to start their journeys in Zanzibar and cross east Africa rather than tackle the swamp.
The White Nile loses more than half of its waters to evaporation in the Sudd, but it is replenished by the Sobat River from western Ethiopia as it nears Malakal, just to the south of the Sudanese border. After this, the Nile only receives one more tributary, the seasonal Atbara River to the north of Khartoum, before turning south in a great loop and finally flowing north to Egypt.
The Nile has been dammed in several places. Egypt’s Aswan High Dam is the most famous, and ultimately flooded large parts of Nubia, but Sudan has also built several dams. The Roseires Dam at Ad Damazin on the Blue Nile provides most of the country’s electricity, supplemented by a dam at Jebel Aulia on the White Nile just south of Khartoum. A huge new dam was inaugurated at Meroë near the Fourth Cataract in 2009, displacing more than 60,000 people.
-- Source : bradtguides